International Scientific Journal

Thermal Science - Online First

online first only

Influence of temperature on physical and mechanical properties of a sedimentary rock: Coal measure mudstone

Determining the physical and mechanical behavior of sedimentary rocks is one of the most common challenges in deep rock mass engineering. Experiments were conducted to study the physical and mechanical properties of coal measure mudstone with scanning electron microscope, x-rays diffraction and uniaxial compression testing. The results show that temperature has a significant effect on the physical and mechanical properties of coal measure mudstone. The presence of clay minerals in the evaluated mudstone contributes to the unique characteristics seen at high temperature. The mudstone experiences obvious color changes on the surface as temperature rises. This is mostly attributed to the iron-bearing clay minerals. Internal color change is caused by thermal decomposition of kerogen associated with the clay minerals. As the major clay mineral in mudstone, kaolinite undergoes significant phase changes at high temperatures, which leads to changes in mechanical properties. From 25℃ to 200 ℃, due to the evaporation of absorbed water from the clay minerals, the strength of the mudstone increases significantly. As the temperature continues to rise beyond this, water evaporation continues and the rock strength increases gradually from 200℃ to 400 ℃. When the temperature reaches 400 ℃, this mudstone was strengthened as a result of decomposition of the kaolinite and thermal expansion of crystalline minerals. Above 600℃, dehydration of the clay minerals ends while thermal cracking initiates gradually, which results in decreasing strength.
PAPER REVISED: 2019-06-15
PAPER ACCEPTED: 2019-06-22
  1. Yuan, Zhang, et al. Heat transfer analysis of surrounding rocks with thermal insulation layer in high geothermal roadway, Thermal Science, 23(2019), 2A, pp. 777-790.
  2. Zhang, Yuan, et al. Unsteady temperature field of surrounding rock mass in high geothermal roadway during mechanical ventilation, J. Cent. South Univ., 24 (2017), 2, pp. 374-381.
  3. Yang, Lintao, et al. Effect of high temperatures on sandstone - a computed tomography scan study, Int. J. Phys. Model. Geo., 17 (2017), 2, pp. 75-90.
  4. Zhang, Yuan, et al. Uniaxial compressive strength and failure characteristics of arkosic sandstone after thermal treatment, Thermal Science, 2019, doi: 10.2298/TSCI180909026Z.
  5. Zhu, Haiyan, et al. A fracture conductivity model for channel fracturing and its implementation with Discrete Element Method, J. Petrol. Sci. Eng., (2019), 172: pp. 149-161.
  6. Liu, Ruixue, et al. Influence of temperature on mechanical properties of mudstone (in Chinese), Mining R. & D., 32 (2012), 4, pp. 97-99, 118.
  7. Zhang, Lianying, et al. Experimental research on thermal damage properties of mudstone at a high temperature (in Chinese), J. Min. & Safety Eng., 29 (2012), 6, pp. 853-858.
  8. Zha, Wenhua,et al. Experimental study of mechanical characteristics of coal-serial sandy mudstone at different temperatures (in Chinese), Chinese J. Rock Mech. Eng., 33 (2014), 4, pp. 809-816.
  9. Zhang, Lianying, et al. Meso-structure and fracture mechanism of mudstone at high temperature, Int. J. Min. Sci. Tech., 24 (2014),4, pp. 433-439.
  10. Xianfeng, Liu, et al.: Mechanical behavior of an Australian mudstone subjected to heating treatment at high temperatures. ISRM Congress 2015 Proceedings - 13th International Symposium on Rock Mechanics, Montreal, Canada, 2015, Vo. 1.
  11. R. E., Grim; W. F. Bradley. Investigation of the effect of heat on the clay minerals illite and montmorillonite, J. Am. Ceram. Soc., 23 (1940), 8, pp. 242-248.
  12. Chandrasekhar, S. Influence of metakaolinization temperature on the formation of zeolite 4A from kaolin, Clay Minerals, 31 (1996), 2, pp. 253-261.
  13. Mario, García-González, et al. Generation and expulsion of petroleum and gas from Almond formation coal, Greater Green River Basin,Wyoming, AAPG Bulletin, 81(1997), 1, pp. 62-81.
  14. P. K., Gautan, et al. Study of strain rate and thermal damage of Dholpur sandstone at elevated temperature, Rock Mech. Rock Egn., (2016), 49, pp. 3805-3815.
  15. Hajpál, M.; Török, Á. Mineralogical and colour changes of quartz sandstones by heat, Environmental Geology, 46 (2004), 3-4, pp. 311-322.
  16. H., Tian, et al. Physical and mechanical behavior of claystone exposed to temperature up to 1000℃, Int. J. Rock Mech. Min. Sci., (2014), 70, pp. 144-153.
  17. Viola, Becattini, et al. Experimental investigation of the thermal and mechanical stabilityof rocks for high-temperature thermal-energy storage, Applied Energy, (2017), 203, pp. 373-389.
  18. Wang, Ping, et al. Study on the rule of variation of red-mudstone from Jiangxi on heating (in Chinese), Acta Mineralogical Sinica, 21 (2001), 3, pp. 505-507.
  19. Wang, Min, et al. Pyrolysis products characteristics and kinetic analysis of coal and mudstone during thermal cracking process in the closed system (in Chinese), Acta Sedimentologica Sinica, 29 (2011), 6, pp. 1190-1198.
  20. Wang, Qing, et al. Characteristics analysis in the process of kerogen pyrolysis (in Chinese), Acta Petrolei Sinica, 33 (2017), 3, pp. 507-514
  21. C.Y., Chen, et al. Microstructural evolution of mullite during the sintering of kaolin powder compacts, Geramics International, (2000), 26, pp. 715-720.
  22. Gulgun, Yilmaz. The effects of temperature on the characteristics of kaolinite and bentonite, Scientific Research and Essays, 9 (2011), 6, pp. 1928-1939.
  23. Ilić, B. R., et al. Thermal treatment of kaolin clay to obtain metakaolin, Hemijska Industrija,. 64 (2010), 4, pp. 351-356.